Package for copy sheets



Jan. 7, 1969 w. P. TAYLOR 3,420,405

PACKAGE FoR COPY SHEETS Filed Aug. 4, 1966 I. In, .m

III! I I I III III/I I II 11] II II]! II [III/II I 1 4- 3/ I I I I I I II I I I 9 I A I United States Patent 3,420,405 PACKAGE FOR COPY SHEETSWilliam P. Taylor, Hamilton, Ohio, assignor to U.S. Plywood-ChampionPapers Inc., a corporation of New York Filed Aug. 4, 1966, Ser. No.570,195 US. Cl. 22125 Int. Cl. B65h 3/58 7 Claims ABSTRACT OF THEDISCLOSURE This invention relates to making copies of images and moreparticularly the intention relates to a package of copy sheets which canbe readily extracted from the package for immediate use in the copyingprocess.

The copy sheets which are packaged in accordance with the presentinvention are of the type described in my copending applications Ser.No. 498,821 filed Oct. 20, 1965, and Ser. No. 570,294 filed Aug. 4,1966. As described in those applications, each copy sheet comprises animpermeable base sheet which is preferably transparent and a very thinporous film on one surface of the base sheet. When used throughout thisdescription and claims, the porous film on the copy sheet embracesdiscontinuous substances capable of sorbing a sensitizing liquid as wellas gels which are swollen by the sensitizing liquid. The porous film ismoistened with sensitizing liquid having the capacity to solvate theporous film and thus change its optical properties under certainconditions of exposure to printed paper. The sensitizing liquid, forcertain film systems, is preferably constituted by water and a solventfor the material of which the film is formed while for other filmsystems, a plain water sensitizer is used.

The copy sheets as thus formed are ready for immediate copying. Whenplaced against a printed cellulosic paper, the sensitizing liquidvaporizes and the vapor selectively diffuses or migrates into theprinted paper to a greater extent in its non-image areas than in itsimage areas, thus creating a disparate amount of moisture retained inthe corresponding areas of the copy sheet overlying the image areas ofthe printed paper. The different conditions thus created in the areasoverlying the image and non-image areas of the printed sheet cause suchchanges in the optical properties of the copy sheet as to bring out animage. More succinctly stated, when the copy sheet is held against thepaper for a few seconds, a discernible mirror image will appear on thesurface of the copy sheet which can be read through the reverse side ofthe copy sheet if it is transparent.

The process involves the sensitizing of the-copy sheets with ratherminute quantities of liquid. The film which retains the moisture is verythin and care must be exercised to avoid its being either too wet or toodry. If too dry, obviously the process will work imperfectly because ofthe insufficient moisture to effect the change in optical properties ofthe film. If too wet, it will cockle the printed paper to which it isapplied, the process will take too much time to be feasible, and it maynot even work at all if the copy sheet is so wet that the properconditions for vapor diffusion are not present.

It is possible to moisten the sheets at the time of use, that is to say,immediately prior to their application to the printed sheet, but thisoperation requires carrying moistening equipment as Well as thesensitizing liquid along with the copy sheets wherever the copy sheetsare 3,420,405 Patented Jan. 7, 1969 to be used. Further, as indicatedabove, a certain amount of precision is required in the moistening andthe less skill-ed opera-tors might achieve rather indifferent ornegative results. To provide a copy sheet which can be successfully usedby even the most casual operators, it has been an objective of theinvention to provide a package of premoistened copy sheets, the copysheets being easily extracted from the package and ready for immediateuse when extracted.

It has been a further objective of the invention to provide such apackage in which the copy sheets will have a long shelf life. In thisregard, even the best of moistureproof films will permit the escape,over a period of time, of at least some vapor, and even if there is noescape of vapor in the package, there will be a diffusion of vapor fromthe porous film to any overlying packaging material which might rob theporous film of enough moisture to decrease the effectiveness of the copysheet.

To achieve the objectives of the invention, I provide a package of copysheets in which each copy sheet has an overlying cover sheet, the coversheet having on the surface adjacent the copy sheet a storage layerwhich holds a substantial amount of the sensitizing liquid. A packagemay be formed as a stack of copy sheets alternating with cover sheets oralternatively the package may be formed as a roll of a web having themoisture containing layer with copy sheets serially placed on the web.The copy sheets, in this embodiment, could, of course, be in the form ofa single web with the container having means for cutting copy sheets ofan appropriate length from the web.

The several objectives and features of the invention will become morereadily apparent from the following detailed description taken inconjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of a package formed in accordance with theinvention,

FIG. 2 is a disassembled cross sectional view of the package taken alonglines 2-2 of FIG. 1 and FIG. 3 is a cross sectional view through analternative form of the invention.

Referring to FIGS. 1 and 2, the package indicated at 10 has a pluralityof copy sheets 11, each having a sensitized film 12 on its uppersurface. Overlying each copy sheet is a cover sheet 13 having a storagelayer 14 containing the sensitizing liquid. The film 12 is very thin,preferably much less than one mil in thickness, as, for example, 0.0001inch thick, whereas the storage layer 14 may well be at least 0.001 inchthick in order to contain a sufficient quantity of moisture to maintainthe film 12 in a properly sensitized condition. As can be observed fromFIG. 2, the moisture con-taining layer 14 has a margin 15 around itsperiphery which projects beyond the peripheral edge 16 of the sensitizedfilm to insure against the drying out of the sensitized film around itsmarginal edge portions.

The cover sheets 13 have peripheral margins 17 eX- tending well beyondthe edges of the copy sheets 11. The margins 17 are sealed together on acontinuous line 18 (FIG. 1) so as to encapsulate a copy sheet betweenadjacent cover sheets. Preferably, the peripheral margins 17 are foldedupon themselves as at 19 to compensate at the edges of the package forthe bulk of the copy sheet and the moisture containing layer 14 of thecover sheet. Thus, the material thickness at the edge of the package isapproxi mately the same as the material thickness through the centralportion of the package.

The lowermost sheet 20 may simply be an impervious sheet of the samematerial as the cover sheets 13 but without having any moisturecontaining layer 14. The sheet 20 is sealed around its edges along theline 18 to package the lowermost copy sheet.

As illustrated in FIG. 1, tabs 22 may be associated with alternate coversheets at one edge of the package and tabs 23 associated with coversheets at an opposite edge of the package to facilitate the removal ofthe individual cover sheets to expose a copy sheet. By alternating thetabs, each tab is made more accessible. The tabs may be formed asseparate inserts sealed to the cover sheets during the formation of thepackage or, alternatively, they may be integral extensions of the coversheets.

The moisture containing storage layer is preferably a swollen,gelatinous but non-sticky material such as gelatin which has been tannedenough to make it insoluble, or polyvinyl alcohol which has beeninsolubilized by poly (vinyl methyl ether-maleic anhydride), orpolyvinyl acetate which has been given a controlled amount of waterreceptivity by combining it with a hydrophilic colloid, or celluloseacetate which has been swollen or partially hydrolized, or regeneratedcellulose, or silica gel, or the like. The cover sheet to which thelayer 14 is adhered is preferably a sheet of aluminum foil coated with aheat sealing plastic. The cover sheet may, however, be a material suchas saran, polyethylene, polystyrene, or the like, and such cover sheetmay, if necessary or desired, be coated with a substance to provide amoisture barrier. If a thermoplastic material is used, there is no needto apply the coating of heat sealing plastic for the material itself issufficiently thermoplastic to permit the joining of the cover sheetedges along the line 18 through the application of known sealingtechnique utilizing heat, ultrasonic energy or the like. The seal maypreferably be made peelable in accordance with known techniques tofacilitate the opening of the package. The moisture containing layer 14may be secured to the sheet by any suitable adhesive.

In the operation of the invention, before the package is completed bysealing it around its periphery along line 18, the moisture storagelayer 14 and the sensitized film 12 are moistened to the extent of theircapacity to receive the sensitizing liquid but Without free liquid inthe form of droplets or a continuous layer on the surface of either themoisture containing layer or porous film. The copy sheets and coversheets are interleaved and heat sealed as described to form the package.At any time during the period of its useful life it is desired to makecopies, the operator tears away the topmost cover sheet, therebyexposing the copy sheet. The copy sheet preferably has in its porousfilm suflicient moisture to require it to be dried for five or tenseconds before application of the copy sheet to the printed paper to bereproduced. This five or ten second drying time gives the operator abrief period in which to remove the cover sheet and to align the copysheet with the printed paper before it is actually held in contact withthe printed paper. It Will be found useful to leave the copy sheet inposition at the top of the package when applying the copy sheet to theprinted paper so that the copy sheet will be smooth when applied to theprinted paper and will permit the use of the remaining portions of thepackage to apply the slight pressure of the copy sheet to the paperwhich is required for uniformity of results.

After a few more seconds, the copy sheet is removed from the printedpaper and a discernible image will appear on the copy sheet, all asdescribed in my copending applications.

An alternative form of the invention is illustrated in FIG. 3. In thisform of the invention, the copy sheeting and cover sheeting are formedas described in the first embodiment except for the length of the coversheet.

The package of FIG. 3 comprises a container having rigid end walls 31,side walls 32, a top wall 33, and a bottom wall 34. The bottom wall 34is provided with two spaced slots 35 and 36 extending transverselyacross the width of the container. A pair of spindles 37 and 38 aremounted on spaced parallel axes for rotation between the side walls 32of the container. The spindle 38 has a crank handle 39 projectingoutside of the container by which the spindle can be rotated. Wrappedabout the spindle 37 are three plies of materials. The first ply is anelongated web 40 forming the cover sheeting, the web '40 having amoisture containing storage layer 41 adhered to one of its surfaces. Thesecond ply is constituted by a series of copy sheets 42, each having amoisturized porous film 43 positioned against the moisture containinglayer 41 of the cover sheeting. The third ply is a web 44 of impermeableplastic such as polyethylene, polypropylene, polystyrene, or the likewhich covers the copy sheets. Preferably, the cover sheet andimpermeable web have longitudinal margins which project beyond thelongitudinal edges of the copy sheets and are preferably heat sealedalong the overhanging marginal edges to minimize the possibility ofevaporation of moisture along the sides of the roll of material. Thethree plies of material are wound on the spindle 37 as shown and are fedthrough the slot 35. The impermeable web is fed across the bottom of thecontainer and passes back into the container through the slot 36 and iswound around the spindle 38. A knife edge 45 is fixed to the corner ofthe container adjacent the slot 35 to permit the tearing away of usedportions of the cover sheet. In the operation of the package of FIG. 3,the user turns the crank 39 in a clockwise direction as viewed in FIG. 3to wind a portion of the impermeable web 44 around the spindle 38,thereby drawing a copy sheet with its cover sheet across the bottom ofthe container. The cover sheet is pulled away from the impermable web toexpose the copy sheet and that portion of the cover sheet is pulledagainst the knife edge 45 to sever it from the web. The exposed copysheet is applied to a printed paper as described above to form an imageWhere it is known or likely that either of the packages described abovewill have to be stored over a long period of time, it may be founddesirable to enclose the packages in a glass, plastic, or metalcontainer in which a supply of this sensitizing solvent is provided tomaintain an essentially saturated atmosphere so that the moisture withinthe individual packets has little tendency to diffuse outwardly.

I claim:

1. A package of copy sheets comprising,

at least one impermeable base sheet having a moistened porous film onone of its surfaces, said film being capable of having its opticalproperties changed upon diffusion of said moisture to a printed sheet soas to reproduce the printing in said copy sheet, and

a cover sheet overlying said copy sheet, said cover sheet having amoisture containing storage layer on one surface thereof adjacent saidfilm, said cover sheet being removable from said copy sheet film forexposure of said film to said printed sheet.

2. A package according to claim 1 in which said porous film issubstantially less than one mil thick and in which said storage layer isat least approximately one mil thick.

3. A package according to claim 1 in which said porous film is notthicker than approximately 0.0001 inch and in which said storage layeris at least 0.001 inch thick.

4. A package of copy sheets comprising,

a plurality of copy sheets alternating with a plurality of cover sheets,

each said copy sheet having a thin porous film on one surface thereof,

each said cover sheet having a moisture containing storage layer,thicker than said film, on a surface facing said porous film, said coversheets having peripheral margins projecting beyond the peripheral edgesof said copy sheets, said margins being sealed together around theperiphery of said package.

5. A package according to claim 4 in which said margins are folded uponthemselves to provide a thick edge whereby the material thickness at theedge of the package is approximately the same as that through thecentral portion of the package.

6. A dispensing package for copy sheets comprising,

an elongated web having a moisture containing storage layer on onesurface thereof,

copy sheet material covering said storage layer and constituted by animpermeable base sheet and a thin porous film facing said layer,

an impermeable web on said elongated Web and overlying said copy sheetmaterial,

a container having a dispensing opening,

a spindle rotatably mounted in said container,

21 take up spindle rotatably mounted in said container on an axisparallel to said first named spindle and adapted to receive saidimpermeable web, and

said web and film being wound on said first named spindle.

7. A dispensing package for copy sheets comprising,

an elongated web having a moisture containing storage layer on onesurface thereof,

copy sheet material covering said storage layer and constituted by animpermeable base sheet and a thin porous film facing said layer, saidcopy sheet material is formed as separate sheets serially mounted onsaid web,

a container having a dispensing opening,

a spindle rotatably mounted in said container, and

said web and film being wound on said spindle.

References Cited UNITED STATES PATENTS 695,488 3/1902 Post. 3,049,8368/1962 Weissman 206-47 3,203,798 8/1965 Muller 9649 3,255,007 6/1966Kosar 96--4 MARTHA L. RICE, Primary Examiner.

US. Cl. X.R.

